Interface arrangement for use with consumer devices

ABSTRACT

A data processing system includes a head for electro-optically reading coded indicia to generate digital decoded data in a predetermined data exchange format. An interface arrangement is used for connecting the head to any selected one of a plurality of electronic devices having individual data processors. Thus, a common data exchange format is established for all the devices, and conversion circuitry is employed for converting the predetermined data exchange format to the common format. The conversion circuitry is operatively connected between the head and the selected device.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 08/443,850filed May 18, 1995, now abandoned, which is related to two concurrentlyfiled U.S. patent application Ser Nos. entitled "Interface Arrangementfor Use With Coded Data Processing Systems" and "Snap-Apart Housing ForUse In Interface Arrangement For Coded Data Processing Systems",respectively.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention generally relates to apparatus for electro-opticallyreading indicia having parts of different light reflectivity, forexample, bar code or matrix array symbols, and, more particularly, to aninterface arrangement for, and a method of, making such apparatuscompatible with different consumer devices, such as video cassetterecorders, facsimile machines, video cameras and television boxes,having data processors which operate with different data exchangeformats, or which operate with an industry standard format.

2. Description of the Related Art

Various optical readers and optical scanning systems have been developedheretofore for reading indicia such as bar code symbols appearing on alabel or on the surface of an article. The bar code symbol itself is acoded pattern of indicia comprised of a series of bars of various widthsspaced apart from one another to bound spaces of various widths, thebars and spaces having different light reflecting characteristics. Thereaders in scanning systems electro-optically transform the graphicindicia into electrical signals, which are decoded into alphanumericcharacters that are intended to be descriptive of the article or somecharacteristic thereof. Such characteristics are typically representedin digital form and utilized as an input to a data processing system forapplications in point-of-sale processing, inventory control and thelike.

Scanning systems of this general type have been disclosed, for example,in U.S. Pat. Nos. 4,251,798; 4,369,361; 4,387,297; 4,409,470; 4,760,248;4,896,026, all of which have been assigned to the same assignee as theinstant application. As disclosed in some of the above patents, oneembodiment of such a scanning system resides, inter alia, in ahand-held, portable laser scanning device supported by a user, which isconfigured to allow the user to aim the scanning head of the device, andmore particularly, a light beam, at a targeted symbol to be read.

The bar code symbols are formed from bars or elements typicallyrectangular in shape with a variety of possible widths. The specificarrangement of elements defines the character represented according to aset of rules and definitions specified by the code or "symbology" used.The relative size of the bars and spaces is determined by the type ofcoding used as is the actual size of the bars and spaces. The number ofcharacters (represented by the bar code symbol) is referred to as thedensity of the symbol. To encode the desired sequence of the characters,a collection of element arrangements are concatenated together to formthe complete bar code symbol, with each character of the message beingrepresented by its own corresponding group of elements. In somesymbologies, a unique "start" and "stop" character is used to indicatewhen the bar code begins and ends. A number of different bar codesymbologies exist, these symbologies including UPC/EAN, Code 39, Code128, Codeabar, and Interleaved 2 of 5, etc.

In the laser beam scanning systems known in the art, the laser lightbeam is directed by a lens or other optical components along the lightpath toward a target that includes a bar code symbol on a surface of thetarget. A moving-beam scanner operates by repetitively scanning thelight beam in a line or series of lines across the symbol by means ofmotion of a scanning component, such as the light source itself or amirror disposed in the path of the light beam. The scanning componentmay either sweep the beam spot across the symbol and trace a scan lineacross the pattern of the symbol, or scan the field of view of thescanner, or do both.

Bar code reading system also include a sensor or photodetector whichdetects light reflected or scattered from the symbol. The photodetectoror sensor is positioned in the scanner in an optical path so that it hasa field of view which ensures the capture of a portion of the lightwhich is reflected or scattered off the symbol. The captured light isdetected and converted into an electrical signal. Electronic circuitryand software decode the electrical signal into a digital representationof the data represented by the symbol that has been scanned. Forexample, the analog electrical signal generated by the photodetector isconverted by a digitizer into a pulse width modulated digitized signal,with the widths corresponding to the physical widths of the bars andspaces. Such a digitized signal is then decoded, based on the specificsymbology used by the symbol, into a binary representation of the dataencoded in the symbol, and subsequently to the alphanumeric charactersso represented.

The decoding process of known bar code reading systems usually works inthe following way. The decoder receives the pulse width modulateddigitized signal from the digitizer, and an algorithm, implemented inthe software, attempts to decode the scan. If the start and stopcharacters and the characters between them in the scan were decodedsuccessfully and completely, the decoding process terminates and anindicator of a successful read (such as a green light and/or an audiblebeep) is provided to the user. Otherwise, the decoder receives the nextscan, performs another decode attempt on that scan, and so on, until acompletely decoded scan is achieved or no more scans are available. Sucha signal is then decoded according to the specific symbology into abinary representation of the data encoded in the symbol, and to thealphanumeric characters so represented.

Moving-beam laser scanners are not the only type of optical instrumentcapable of reading bar code symbols. Another type of bar code reader isone which incorporates detectors based on charge coupled device (CCD)technology. In such readers the size of the detector is typicallysmaller than the symbol to be read because of the image reduction by theobjective lens in front of the CCD. The entire symbol is flooded withlight from a light source such as light emitting diodes (LED) in thescanning device, and each CCD cell is sequentially read out to determinethe presence of a bar or a space.

The interfacing of scanning heads with consumer devices having dataprocessors utilizes arrangements such as described in U.S. Pat. No.5,258,604. In such prior art arrangements, the interface arrangement hascircuitry for storing and applying an identification code representingthe identity of a selected one of a plurality of input/output (I/O)devices to the decoder of the scanner, for operating the decoder, andfor transferring decoded signals and command signals between theselected one of the I/O devices and the decoder.

SUMMARY OF THE INVENTION OBJECTS OF THE INVENTION

It is a general object of the present invention to provide an improvedinterface arrangement for making consumer devices compatible with a barcode data processing system.

It is another object of the invention to provide an accessory that canbe used to quickly and easily interconnect and disconnect an all-purposescanning head with a selected one of a plurality of consumer deviceseach having a different data processor.

It is a further object of the present invention to provide abidirectional communication interface for connecting a scanning head toa processor-based consumer device having a predetermined data exchangeformat.

It is an even further object of the invention to provide a method whichcan be used to accomplish one or more of the above objectives.

Additional objects, advantages and novel features of the presentinvention will become apparent to those skilled in the art from thisdisclosure, including the following detailed description, as well as bypractice of the invention.

While the invention is described below with reference to preferredembodiments, it should be understood that the invention is not limitedthereto. Those of ordinary skill in the art having access to theteachings herein will recognize additional applications, modificationsand embodiments in other fields, which are within the scope of theinvention as disclosed and claimed herein and with respect to which theinvention could be of significant utility.

FEATURES OF THE INVENTION

Briefly described, and in general terms, the present invention providesan interface arrangement or accessory for processing and translating barcode and control signals, including digitized bar code signals, intodata configurations or packets (formats or protocols) recognizable byone of a plurality of different processor-based consumer devices, suchas video cassette recorders, facsimile machines, video cameras andtelevision boxes used with a scanner for reading bar code symbols.Utilizing the arrangement of the present invention, a user has theability to quickly and easily interface an all-purpose, generic scanninghead of the scanner with a selected consumer device by selecting theappropriate one of a plurality of different interface arrangements thatis physically designed to plug directly into a connector on the consumerdevice, thereby automatically providing compatibility with the scanninghead.

More specifically, in a bar code data processing system including ascanning head for reading coded symbols and decoding such symbols intodigital signals, and a consumer device having a processor with apredetermined data exchange format for receiving and transmittingsignals with peripheral equipment, the present invention provides anarrangement for interconnecting the consumer device and the scanninghead, including first connection means for direct connection to theconsumer device; second connection means for direct connection to a headcable connected to the scanning head; and conversion means forconverting the digital decoded signals from the scanning head intodigital data signals having a format compatible with the consumerdevice's predetermined data exchange format.

The present invention further provides a method of transferring databetween a processor-based consumer device having a predeterminedinput/output data exchange format, and a bar code reader head whichreads and converts coded symbols into decoded signals representinginformation encoded in the symbols, by decoding the data representingthe information represented by the symbol in the form of serial data;transferring the serial data along a single communication line or bus;and removably connecting the communication line to the consumer device.

The novel features and characteristics of the invention are set forth inthe appended claims. The invention itself, however, as well as otherfeatures and advantages thereof, will be best understood by reference toa detailed description of a specific embodiment, when read inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a highly simplified diagrammatic view of an interfacearrangement according to the present invention for interconnecting a barcode data processing system with one of a plurality of consumer devices;

FIG. 2 is a perspective view of one embodiment of the interfacearrangement according to the present invention;

FIG. 3 is a broken-away top plan view of a second embodiment of theinterface arrangement according to the present invention;

FIG. 4 is a broken-away bottom plan view of the embodiment of FIG. 3.

FIG. 5 is a block diagram of the interconnection of certain componentsof the interface arrangement; and

FIG. 6 is an elevational view of a head cable used with the interfacearrangement.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention relates to electro-optical readers of the type generallydescribed in the above identified patents for reading bar code symbols.As used in this specification and the claims, the term "bar code symbol"is intended to be broadly construed and to cover not onlyone-dimensional symbol patterns composed of alternating bars and spacesarranged in a row, but also other graphic patterns, such as dot ortwo-dimensional matrix array patterns, as well as alpha-numericcharacters and, in short, any indicia having portions of different lightreflectivity.

As a preferred embodiment, we describe the implementation of the presentinvention in a hand-held, laser-scanning, bar code reader unit such asillustrated in FIG. 1. This hand-held device of FIG. 1 is generally ofthe style disclosed in U.S. Pat. No. 4,760,248, issued to Swartz, etal., assigned to Symbol Technologies, Inc., and also similar to theconfiguration of a bar code reader commercially available as part numberLS 2000 or LS 3000 from Symbol Technologies, Inc. Alternatively, or inaddition, features of U.S. Pat. No. 4,387,297 issued to Swartz, et al.,or U.S. Pat. No. 4,409,470 issued to Shepard, et al., both such patentsbeing assigned to Symbol Technologies, Inc., may be employed inconstructing the bar code reader unit of FIG. 1. These U.S. Pat. Nos.4,760,248; 4,387,297 and 4,409,470 are incorporated herein by reference.

Referring now to the drawings, reference numeral 100 generallyidentifies a hand-held, gun-shaped, retro-reflective scanner head orreader unit having a barrel 101 and a pistol-grip handle 102. Amanually-operable trigger 154 is situated below the barrel 101 on anupper, forwardly-facing part of the handle 102. As known from theabove-identified patents incorporated by reference herein, a lightsource component, typically, but not necessarily, a laser diode 158 ismounted inside the head 100.

The operation of the reader unit 100 is as follows: An outgoing lightbeam 151 is generated in the reader 100, by the laser diode 158 or likelight source. The beam 151 is directed outwardly through a window 159that faces the indicia, e.g., a bar code symbol 170 located at areference plane P spaced at a distance from the front of the readerunit. The beam 151 is either immediately transmitted through the window159 as shown, or is directed to a generally planar reflector which, inturn, reflects the beam 151 through the window. The outgoing light beam151 is scanned by scanning drive component 160 in a fixed linear patternwhich produces a visible scan line on the symbol. The user positions ororients the hand-held unit so this scan line traverses all of the barsof the symbol to be read.

Reflected light 152 from the symbol is detected by a light-responsivedevice or detector 146 in the reader unit, producing serial electricalsignals to be processed for decoding the information contained in thebar code. The movable trigger 154 is employed to allow the user toactivate the light beam 151 and/or associated signal processing andcommand circuitry only after the user has pointed the unit at the symbolto be read, thereby ensuring that the correct target is read if there ismore than one target in the field of view, and also saving battery lifeif the unit is self-powered.

The reader unit 100 is designed to be aimed at a bar code symbol by theuser from a position where the reader unit 100 is spaced from thesymbol, i.e., not touching the symbol or moving across the symbol.Typically, this type of hand-held bar code reader is specified tooperate in the range of perhaps several inches.

A lightweight plastic housing 155 contains the laser diode 158, thedetector 146, optics 157, the scanning drive component 160, signalprocessing circuitry 165, decoder circuitry 163, and a centralprocessing unit (CPU) 140, as well as batteries 162. Thelight-transmissive window 159 at the front end of the housing 155 allowsthe outgoing light beam 151 to exit and the incoming reflected light 152to enter. A keyboard 148 and a display 149 are also mounted on thehousing.

As seen in FIG. 1, the optics include a suitable lens 157 (or multiplelens system) used to collimate and focus the scanned beam 151 onto thebar code symbol at the reference plane, and this same lens 157 may beused to focus the reflected light 152 onto the detector 146. The lightsource 158 is positioned to introduce the emitted light beam into theoptical axis of the lens 157 by appropriate beam-shaping structure whenthe trigger 154 is pulled. If the light produced by the source 158 isnot visible, an aiming light may be included in the unit to introduce avisible beam into the light path coaxially with the lens 157. The aiminglight, if needed, produces a visible light spot which is scanned justlike the laser beam 151. The user may employ this visible light to aimthe reader unit at the symbol before pulling the trigger 154 to activatethe scanning.

The photodetector 146 generates an electrical analog signal indicativeof the variable intensity of the reflected light 152. This analog signalis converted into a digitized signal by a digitizer circuit 165. Thisdigitized signal is transferred to a decoder circuit or module 163located interiorly of the head 100. The decoder circuit 163 decodes thedigitized signal into a decoded signal or data represented by (encodedin) the symbol, representing such data in digital form, such as ASCIIcharacters. The digitizer circuit 165, the decoder circuit 163 and theCPU 140 are all mounted on a printed circuit board 161 within the head100. This digital decoded data is then formatted into a communicationspacket according to a protocol procedure, and transmitted along anexternal head cable 170, designated in FIG. 1 as a "ZIF" cable, andseparately illustrated in FIG. 6. An external consumer device 190,usually a computer having a data processor with a predetermined dataexchange format, serves mainly as a data store in which the decoded datagenerated by the decoder circuit 163 is stored for subsequentprocessing.

As described so far, the reader unit or head 100 is customized to eachconsumer device. Since different consumer devices have different dataexchange formats for their microprocessors, each head 100 isspecifically designed to work only with one consumer device. This is notdesirable, especially in environments with multiple consumer devices.

According to the present invention, an interface arrangement orso-called "smart cable" 200 is connected between the head cable 170 andany selected consumer device 190. FIG. 2 illustrates a perspective viewof one embodiment of the interface arrangement 200 according to thepresent invention. As depicted in FIGS. 2-4, the arrangement 200includes a generally parallelepiped housing having an upper part 202, alower part 204, and a printed circuit board 206 mounted between theparts in the housing. As shown in FIG. 4, a microcontroller 208 ismounted on at least one side of the circuit board 206. As shown in FIG.5, a communications circuit 212 consisting of multiple integratedcircuit chips is preferably mounted on both sides of the circuit board206. A female-type RJ modular connector 210 is mounted at one end of thehousing.

As shown in FIG. 6, the head cable 170 has a connector 171 at one endwhich is removably connected to the bar cede reader unit 100 and iselectrically connected to the decoder circuit 163. The head cable 170transfers the decoded data in packet form. The cable 170 has a male-typeRJ connector 172 permanently connected to the opposite end thereof. Thecable 170 has a coiled section 173 intermediate its ends.

Conversion means are provided on the arrangement 200. The conversionmeans includes the microcontroller 208 and the communications hardwarecircuitry 212. The conversion means is operative for converting theformat of the data packets into digital signals whose data exchangeformat is compatible with the consumer device.

A consumer device cable 220 having a plurality of individual conductorshas one end 222 permanently fastened to the housing 202, 204. Theconsumer device cable 220 extends exteriorly thereof to an opposite endconsumer connector 230 for removably connecting the microcontroller 208and the communications hardware circuitry to the consumer device 190.

A power supply connector 240 and power switch are also provided for thearrangement. The power supply connector 240 is accessible at the side ofthe housing.

In accordance with this invention, a general, all-purpose scanning headcan be manufactured and supplied to many customers. Depending on theconsumer device present at a customer site, the appropriate interfacearrangement can be provided.

The consumer device can be any processor-based equipment, e.g., as shownin FIG. 1, a video cassette recorder 190A, a facsimile machine 190B, avideo camera 190C and a television box 190D.

In further accordance with this invention, the aforementioned consumerdevices can be manufactured with an industry standard interface. Forexample, a currently available industry standard serial interface isknown as the IEEE 1394 bus (also known as FIREWIRE). This interfacecould advantageously be used to connect the head 100 to any of the abovecomputers and consumer electronic products. The IEEE 1394 bus handlesisochronous data at speeds of 100, 200, or 400 Mbits/sec.

The conversion circuitry for converting the serial decoded data packetsgenerated in the head 100 to the FIREWIRE interface can advantageouslybe provided in the smart cable accessory 200 or, if desired, directly ona printed circuit board within the head. Thus, an electro-opticalscanner may be connected to various computers and electronic products sothat information encoded in coded indicia can be exchanged with suchproducts and processed.

While the invention has been illustrated and described as embodied in aninterface arrangement for use with consumer devices, it is not intendedto be limited to the details shown, since various modifications andstructural changes may be made without departing in any way from thespirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can readily adapt it for variousapplications without omitting features that, from the standpoint ofprior art, fairly constitute essential characteristics of the generic orspecific aspects of this invention and, therefore, such adaptationsshould and are intended to be comprehended within the meaning and rangeof equivalence of the following claims.

I claim:
 1. In a data processing system including a head forelectro-optically reading coded symbols to generate digital decoded datain a predetermined data exchange format, and a plurality of electronicdevices having individual data processors, an interface arrangement forconnecting the head to any selected one of the devices, comprising:meansincluding a serial interface for establishing a common data exchangeformat which is identical for all the devices; a housing having oneconnector detachably connected to a head cable connected to the head andanother connector detachably connected to the selected device; and meanswithin the housing for converting the predetermined data exchange formatto said common format, said converting means including microcontrollercircuitry mounted on a printed circuit board within the housing andbeing operatively connected between the head and the selected device forcommunicating serial data between the head and the selected device. 2.The arrangement of claim 1, wherein the head cable has a plug-in,modular-type connector at a remote end away from the head; and whereinsaid another connector of the housing is also a plug-in, modular-typeconnector.
 3. The arrangement of claim 1, wherein the serial interfaceis a bus for bidirectional transfer of isochronous data.
 4. Thearrangement of claim 3, wherein the bus is an IEEE 1394 industrystandard.
 5. A method of connecting a head for electro-optically readingcoded indicia to generate digital decoded data in a predetermined dataexchange format, to any selected one of a plurality of electronicdevices having individual data processors, comprising the stepsof:establishing with a serial interface a common data exchange formatwhich is identical for all the devices; detachably connecting oneconnector to a head cable connected to the head, and detachablyconnecting another connector to the selected device; and converting thepredetermined data exchange format to said common format by mountingmicrocontroller circuitry on a printed circuit board within a housing,and by operating the microcontroller circuitry to communicate serialdata between the head and the selected device.
 6. The method of claim 5,wherein the establishing step is performed with a serial interface busfor bidirectional transfer of isochronous data.
 7. The method of claim6, wherein the bus is an IEEE 1394 industry standard.